Do Printers Believe in Continuous Improvement?

[danremaley]

I've used System Brunner at various times since the early 80s. It had application then (in the 80s) based on the technology used for separation, plate imaging, and press function at that time. However, the system is not as applicable today. If you do an unbiased testing of its principles you will quickly see that they have very limited value in today's production process.
At the present moment I'm on a ferry, but as soon as I reach landfall and get to my home I'll post an example of how these notions of grey balance fail.
In the meanwhile you can read this explanation of the reasons why on my blog:
The Print Guide: Grey Balance Unbalanced – An inconvenient truth

Best, gordo

I have read your "unbalanced" guide- many items simply untrue. Like your quote "as far as I can determine, there has never been a formal, objective, study of the relationship of grey balance targets measured in press sheet color bars and how they relate to the live image content of the press sheet."
www.systembrunner has done many studies based on image content and gray balance measurement. I have several articles by the "Master" Felix Brunner, if you'd like a copy, I'd be happy to enlighten you, after I park my Corvette. . .all the best (color that is).
Dan Remaley
412.889.7643

 

[Deleted member 16349]

Let's see if I can explain- equal amounts of R-G-B equal gray, so the measurement of Cyan(-R filter) Magenta(-G filter) Yelo (-B filter) in equal density value, (i.e. Y.58 M.58 C.58) equals gray. Color is made from both the density and size of the dot, since the pressman can't easily change the size of the dot he increases (or decreases) the density. Without any measuring instrument a pressman "visually" creates gray balance by eliminating any "casts" by increasing or decreasing density, to a point, after which, only new plates, with different dots, will be needed.
I have a great reference piece that shows this relationship, send me an e-mail and I'll return a pdf file.
Dan Remaley
412.889.7643

Dan, you still did not answer the question. I understand grey. I understand dot gain.

I was trying to find out if you understand that the CMY density values for a screen have no direct relationship with the CMY inks when measuring a screen with a densitometer.

I am starting to think that you don't understand that, otherwise I think you would have understood my question.

 

[danremaley]

I guess I don't understand your question? What do you mean "direct relationship"? If you measure print contrast solid vs 75% and you increase density, you change print contrast (the screen tint) so maybe there's some "direct relationship" there? NO?

 

[gordo]

I have read your "unbalanced" guide- many items simply untrue. Like your quote "as far as I can determine, there has never been a formal, objective, study of the relationship of grey balance targets measured in press sheet color bars and how they relate to the live image content of the press sheet."
www.systembrunner has done many studies based on image content and gray balance measurement. I have several articles by the "Master" Felix Brunner, if you'd like a copy, I'd be happy to enlighten you, after I park my Corvette. . .all the best (color that is).

Like I said, what Brunner wrote, and the studies he conducted are from some 40 odd years ago and do not apply to current print production.

Please take each of the issues that I raise in that blog and discredit them. If they are untrue then please explain in what way.

I've done a quite bit of research in this area, in a print shop environment, a vendor environment, as well as less formally in everyday observation (which anyone can do). I know that what I say is heresy, but if you look at the evidence or do the research yourself, I think you'll agree.
I have most, if not all of the published works by Felix Brunner, and I'm sorry, but you're wrong.

His model had some validity back in the day - but not in today's reality.

I'll post an example tomorrow, but again, please challenge the points I raise in my blog on this issue and show me specifically how they are untrue.

Best, gordo

 

[Deleted member 16349]

I guess I don't understand your question? What do you mean "direct relationship"? If you measure print contrast solid vs 75% and you increase density, you change print contrast (the screen tint) so maybe there's some "direct relationship" there? NO?

I will try to come at this from a different direction which might help.

As an example. The press operator measures the CMY density values from the grey patch. The C and Y density values are basically the same and are at the correct values. The M density value is 0.05 lower, so there is a problem with the print of the grey patch.

What specifically is the press operator supposed to do to get the grey patch to the correct grey balance?

 

[gordo]

@ Dan

OK here's an example...

I think that your assertion is that the 3/C grey balance patch in the color bar provides meaningful information about color deviation in the live image area. Its sensitivity makes it an effective early warning flag.

My assertion is that the 3/C grey balance patch in the color bar is virtually useless at providing meaningful information about color deviation in the live image area. Its sensitivity also means that it indicates color shifts that should, in most cases be ignored.

Here's the front page of our local paper (picked up on the ferry yesterday):

Like many newspapers today there is a 3/C grey bar at the foot with reference 1/C black.

Looking closer at the 3/C bar you'll see that the grey balance is obviously whacked:

But the images are fine and don't show the extreme green bias of the 3/C grey:

This is what I would have predicted. And is what I've seen in countless tests.

How do you explain this discrepancy?

BTW, if any forum members still get the newspaper and are interested in this grey balance issue - it's an enlightening experience to monitor the local paper's grey balance patches relative to live image content over a period of time.

best, gordo

 

[gordo]

Dan?

Best, gordo